Make up a persuasive memo that summarizes key information the reader would require in the following scenario:

You are the Lab Coordinator at the Texas Woman's University campus Math and Technology Success Center (Math Lab). The normal working hours are M-F from 8 am - 5 pm. However, less students come to the Math Lab over the summer, so the Math Chair has decided to change the summer hours to 8 am - 3:30 pm. This change will be in effect from May 23rd-August 22nd. It's currently April 21. The Chair has asked you, as Lab Coordinator, to draft memo to the part-time student assistants informing them of this change. In addition, you need to keep in mind that these employees are paid by the hour.

Explains the reasoning behind this change in hours and also assuages the concerns of the employees. Remember that memos are public documents and you therefore cannot just blame the Chair.